Coating Makes Steel Tougher, Keeps Microbes From Sticking
More and more objects are getting superhydrophobic coatings that make liquids bounce right off. Surfaces with complex nanoscopic structures that prevent wetting will soon be deployed on wind turbine blades and aircraft wings to prevent ice from sticking, and even concrete is being doped with superhydrophobic compounds to help it last decades longer.
Much still needs to be done, though, to strengthen these coatings because any damage can remove the ability to repel liquids. Such an advance is hugely important since there are potentially life-saving healthcare applications if this hurdle could be overcome with a stable, nontoxic coating for steel. Just imagine if implants, scalpels and other tools used on patients had a surface impossible for infection-causing microbes to cling to.
Now, Joanna Aizenberg and her colleagues at Harvard’s Wyss Institute for Biologically Inspired Engineering have demonstrated a possible solution. They’ve been able to coat stainless steel with nanoporous tungsten oxide, which repels all liquids. What’s more, the surface is extremely tough, maintaining superhydrophobicity even after being scratched with sharp steel objects and diamond.